Of course, I'm sure this hadn't happened in real life to Taylor Swift: I'm sure her parents hadn't had any conflicts!

What I mean is:

In the music video, her "parents" are so blinded in rage and fury for whatever reasons and causes the daughter (played by Taylor Swift) to be skeptical, non-believing, stoic, and jaded in terms of love and be afraid to take the risks of heartbreak, thinking that love will never exist/work/last. Until some random guy (who apparently is a waiter at some diner or restaurant) shows up and proves her wrong. Finally believing in love, she vows to not make the mistake that her parents did.

The song talks about trust and relationships, as trust in both yourself and your loved one is the key to a successful relationship. Never believe that love isn't real, love can be anywhere, and you could be proven wrong at any time. Not all relationships end in heartbreak. Remember what some adults say: "a successful marriage does not have any hardships". It's a total lie, and that's impossible. Every marriage (or in this case, relationship) will have hardships and fights once in a while. You just need to work on it and find a way out.